Electric razor with male and female polygonal cutting elements



Oct. 3, 1967 B. F. CRANE 3,344,517

' ELECTRIC RAZOR WITH-MALE AND FEMALE POLYGONAL CUTTING ELEMENTS Filed Aug. 16, 1965 2 Sheets-Sheet 1- 3a. 22 Z2 56 f? 320 $1 4 20 2/ v HI, f 9 I I 1' I I M A); l' I I 1/ INVENTOR. BE/ETEAM/F CeAA E MM, MM 40M Arraewars Oct. 3, 1967 B. F. CRANE ELECTRIC RAZOR WITH MALE AND FEMALE POLYGONAL CUTTING ELEMENTS 2 Sheets-Sheet 2 Filed Aug. 16, 1965 M2 7 j G 6 lNVENTOR. *6/40 55/27/24 5 6'24:

BY 112M, MM MM Arraewzx;

United States Patent 3,344,517 ELECTRIC RAZOR WITH MALE AND FEMALE POLYGONAL CUTTING ELEMENTS Bertram F. Crane, 2417 N. 59th St., Milwaukee, Wis. 53210 Filed Aug. 16, 1965, Ser. No. 479,889 14 Claims. (Cl. 30-41.9)

ABSTRACT OF THE DISCLOSURE Disclosed herein is an electric shaver having a shaving head comprising a female member having a polygonal bore with means defining a series of cutting edge segments on the margins of the bore and a male member slidable within the female member and including a polygonal portion received in and congruent with the bore and means defining a series of cutting edge segments at the outer margins of the polygonal portion. In addition, means are provided for relatively moving the male and female members to afford a cutting and sliding action.

This invention is a continuation in part of my co-pending application Ser. No. 444,145 filed on Mar. 31, 1965, entitled Electric Razor and now abandoned.

This invention relates to shaving devices and, more particularly, to shaving heads for electric razors.

An object of the invention is to provide an electric shaver with an improved shaving head comprising a first member having a polygonal bore and means defining a series of cutting edge segments at the margins of the bore, and a second member slidably carried within the first member and including a polygonal-shaped raised portion received in and congruent with the bore and means defining a series of cutting edge segments at the outer margins of the raised portion. Means are provided for relatively rotating the first and second members to afford a cutting and slicing action between the corresponding cutting edge segments of the first and second members.

Another object is to provide an improved shaving head whereby the shavers Whiskers are cleanly severed at the skin line by a cutting and slicing action, thus reducing cutting edge Wear, and thus permitting reduction in cutting pressure and, as a result of the reduced cutting pressure, reduction of the size of the motor necessary to operate the shaving head.

Still another object is to provide a shaving head having an externally adjustable device arranged to limit relative movement between the first and second member to afford adjustment of cutting edge spacing.

Further objects are to provide a shaving head which does not employ gears and is therefore quiet, which can be cheaply produced, and which is durable, lightweight and efficient.

Other objects and advantages will become apparent from the following description and the drawings in which:

FIGURE 1 is a plan view of an electric shaver in accordance with the present invention;

FIGURE 2 is a sectional view generally taken along the line 2-2 of FIGURE 1;

FIGURE 3 is an enlarged sectional view taken along line 33 of FIGURE 1;

FIGURE 4 is a plan view of an electric shaver embodying a modified form of the present invention;

FIGURE 5 is a sectional view taken along the line 5-5 of FIGURE 4; and

FIGURE 6 is an enlarged, fragmentary view of a portion of the shaver shown in FIGURE 5.

- Referring now to the drawings and more particularly to FIGURE 2, the electric shaver broadly identified by Patented Oct. 3, 1967 the numeral 10 generally comprises a shaving head 12 carried by the upper portion of a case 14. Any suitable means can be provided to releasably retain the shaving head 12 on the case 14. Power is supplied to the shaving head 12 by a suitable motor 15 housed in a cavity 16 of the case 14 and including an output shaft 17 having an end portion 18 of rectangular cross section and a shoulder 19 between the end portion 18 and the remainder of the shaft 17. The upper portion of the case 14 includes a partition 20 having a hole 21 of larger diameter than output shaft 17 which shaft extends through the hole 21 and beyond the partition 20.

The shaving head 12 generally comprises a first, outer, or female member 22 and a second, inner or male member 24, subsequently to be described, and which is slidably carried within the female member 22. The female member 22 includes a face portion 26 which is adapted to engage the skin of a shaver and which is raised from the remainder of the female member 22.

The female member 22 is provided with means defining a polygonal cutting edge 33 in the plane of the face 26 including a polygonal bore and a series of angularly related surfaces located at the margins of the bore. While the polygonal bore may have any number of sides, the preferred embodiment of the present invention discloses a polygonal bore of triangular configuration, triangular bore 28 including a series of angularly related surfaces with one of such surfaces being a part of the face portion 26. The other inclined surfaces 30 intersect the face portion 26 at the margins of the bore 28 to define a number or series of adjacent and interconnected cutting edge segments 32 forming a single triangular cutting edge 33. Of course, the number of angularly related surfaces corresponds directly to the number of sides of the particular polygonal bore.

The female member 22 also includes a flat or bearing surface 34 located below the face portion 26, and means on the surface 34 defining an annular lip 36 concentric with the triangular bore 28 and including an undercut portion 37. The lip can be either concentric or non-concentric with respect to the triangular bore 28. In the disclosed construction, the annular lip 36 is concentric with the triangular bore 28.

The male member 24 includes a portion 38 having a fiat or bearing surface 40. Sliding movement is affordable between the members 22 and 24 by engagement of the flat surface 40 of male member 24 with the surface 34 of the female member 22. The male member 24 is provided with means defining a polygonal cutting edge 50 corresponding to and cooperable with the cutting edge 33 of the female member 22, as previously described.

The above means includes a polygonal raised portion or part and a series of angularly related surfaces which are located at the periphery of the raised part and which define a cutting edge which is congruent in form with the cutting edge 33 of the female member 22. In the preferred embodiment of the present invention, there is employed a polygonal raised part or portion 42 which is of triangular configuration, and which is raised from the surface 40 and congruent with the bore 28.

The triangular part 42 includes a first surface 44 having a triangular-shaped dished-out portion 45 for reducing friction between the shaving head 12 and the skin of a shaver. The triangular part 42 also includes a series of second or inclined surfaces 46 intersecting the surface 44 at the outer periphery of the raised triangular part 42 to define a number or series of adjacent and interconnected cutting edge segments 48 forming a single triangular cutting edge 50. The cutting edge segments 48 in conjunction with the cutting edge segments 32 of female member 22 provide three sets of corresponding cutting edge segments 32 and 48.

The underside of the male member 24 includes means defining an annular lip 52 which can be either concentric or non-concentric with respect to the triangular raised part 42. In the disclosed construction, the annular lip 52 is concentric with raised part 42 and includes an undercut portion 54.

Relative movement between the members 22 and 24 affords a cutting action bringing together in the plane of the face 26 two cutting edges which cut by a combination of nipping and slicing action. Means are provided for relatively moving the male member 24 with respect to the female member 22. In the disclosed construction, a spring cam 56 is removably carried by the output shaft 17 for rotation therewith. Any suitable means can be provided for rem-ovably connecting the cam or element 56 to the shaft 17. The disclosed construction contemplates an opening 58 of rectangular configuration in cam 56 removably receiving the end portion 18- of the shaft 17 with the cam 56 resting on the shoulder 19. Alternatively, the cam 56 may be held in a spaced position relative to the shoulder 19, rather than resting therein, by action of the spring forws exerted by cam 56 against the annular lips 36 and 52 (hereinafter to be described).

The spring cam 56 includes oppositely extending shorter and longer, arcuate arms 60 and 62 respectively. The shorter arm 60 engages the lip 52 of the male member 24 with the end of the arm 60 pressingly engaging the undercut portion 54. The longer arm 62 engages the lip 36 of the female member 22 with the end of the arm 62 pressingly engaging undercut portion 37. In the disclosed construction, the distance between the ends of the arms 60 and 62 is greater than the sum of the radii of the annular lips 36 and 52. Thus the cam 56, when positioned against the respective lips 36 and 52, is in a flexed condition to provide oppositely reacting forces on the respective lips 36 and 52. As the cam 56 is rotated, these oppositely reacting forces cause relative movement of the male member 24 with respect to the female member 22. In an alternative construction, a spring cam (not shown) removably carried by the shaft 17 and having a single arm including an end engaging the lip 52 can be employed to afford relative movement between the members 22 and 24 in a manner similar to that previously described. Such a cam with a single arm can be employed without the lip 36.

Means are provided for retaining the members 22 and 24 in sliding engagement with each other. In the preferred embodiment such means comprises a series of corresponding holes 66 and 68 in the members 22 and 24 respectively. Bolts 70 are received in the holes 66 and 68. Each hole 68 in the male member 24 is of larger diameter than the bolt 70 for allowing relative movement of the male member 24 with respect to the female member 22. The ends of each bolt 70 extend beyond the underside of the male member 24 and receive a lock washer 72 and a lock nut 74 which provide a clamping force between the members 22 and 24, which clamping force is of sufficient magnitude to retain the members 22 and 24 in sliding engagement with each other.

In the disclosed construction, when the triangular part 42 is centrally located in the bore 28, the cutting edge segments 48 of the male member 24 are spaced about .0025 inch from the corresponding cutting edge segments 32 of the female member 22. Therefore, when two sets of corresponding cutting edge segments 48 and 32 are in contact with each other, the cutting edge segments of the third set are spaced at a sufiicient gap to receive the Whiskers on the skin of a shaver. Rotation of the cam 56 by the motor 15 provides a rocking and sliding movement of the male member 24 relative to the female member 22 to afford a cutting and slicing action along the respective triangular cutting edges 33 and 50. The cutting and slicing action cleanly severs the whiskers disposed between the triangular cutting edges 33 and 50 at the skin line. The cutting or slicing action also lessens cutting edge wear and cutting pressure. The reduced cutting pressure alloWs the use of a smaller sized motor.

In the disclosed construction, means are also provided for limiting the movement of the corresponding cutting edge segments 32 and 48 to limit the minimum spacing between the cutting edge segments 32 and 48. Such means comprises adjustable screw studs 76 threadedly carried by the male member 24 and extending parallel to the first surface 44 between the surface 44 and the flat surface 40 of the portion 38. Each screw stud 76 comprises a stud 78 having one end threadedly received in a threaded hole 80 in the male member 24 and a locking nut 82 for maintaining a given position of stud 78. In the disclosed construction, six screw studs 76 are usedtWo for each cutting edge segment 48 of the male member 24. The ends of screw studs 76 are adapted to contact the female member 22 just below cutting edge 33. The screw studs 76 can be adjusted to maintain various spacing of the respective cutting edge segments 32 and 48. Also the screw studs 76 can be adjusted to maintain no spacing and allow the respective cutting edge segments 32 and 48 to just contact each other. In the disclosed construction a spacing of .0001 inch is desirable to insure that wearing will not occur because of direct engagement between the cutting edge segments 32 and 48.

In the embodiment shown in FIGURES 4-6, the electric shaver is provided with a shaving head 102 carried on the upper portion of a case 104. The shaving head 102 operates in generally the same manner as the shaving head described in the embodiment of FIGURES 1-3. The shaving head 102 includes a first, outer, or female member 122 and a second, inner, or male member 124 which is slidably carried within the female member 122 in the same manner as previously described in the embodiment shown in FIGURES 1-3. The female member 122 is provided with means defining a polygonal bore and a series of angularly related surfaces located at the margins of the bore to define a series of angularly related cutting edge segments 126. The cutting edge segments 126 are joined to the female member 122 'by perpendicular shank portions 128.

The male member 124 is provided with a polygonal raised part or portion received in the polygonal bore of the female member 122 and with means defining a series of cutting edge segments 130 corresponding to and cooperating with the cutting edge segments 126 in a manner as previously described. The cutting edge segments 126 are joined to the male member 124 by perpendicular shank portions 134.

As in the embodiment shown in FIGURES 1-3, the electric shaver 100 includes means for limiting the movement of the corresponding cutting edge segments 126 and 130. In the electric shaver 100, such means comprises an adjusting device carried on the male member 124. The adjusting device 140 is arranged to afford simple and efficient external adjustment of the spacing, if any, between the cutting edge segments 126 and 130. The adjusting device 140 comprises a member 142, which is preferably cylindrical, having a stop in the form of an annular ring or flange 144 which divides the member 142 into first and second portions 146 and 148 respectively.

The cylindrical member 142 is provided with a bore 150 extending therethrough and having a tapered portion 152 which is generally co-extensive with the second portion 148. The second portion 148 is rendered radially expandable by a series of slots 154. More specifically, in the disclosed construction three slots are spaced about the circumference of the second portion 148 and are generally co-exten-sive with the tapered portion 152.

The cylindrical member 142 is slidably carried on the male member 124 with the second portion 148 received in a bore 156 in the shank portion 134 of the male member 124. The diameter of bore 156 is only slightly larger than the diameter of the second portion 148 to provide a close fit therebetween. The annular flange 144 is disposed to contact or engage the inner surface 157 of the female shank portion 128. The first portion 146 of the cylindrical member extends through an enlarged hole or slot 158 in the female shank portion 128. The end of the first portion 146 extends beyond the external wall of the female shank portion 128.

Means are provided for selectively expanding the slotted second portion 148 against the wall of the bore 156 to rigidly connect the adjusting device 140 to the male member 124. In the preferred embodiment, such means comprises an arbor or movable shaft member 160 complementary to and movably received in the bore 150 of cylindrical member 142. The arbor 160 includes a tapered end 162 which cooperates with the tapered portion 152 to expand the slotted second portion 148 upon forcibly moving the arbor 160 into the bore 150.

Means are provided for forcibly moving the arbor 160 into the bore 150. In the preferred embodiment, such means comprises a knurled nut 17 threadedly received on the arbor end 172 which end extends beyond the end of the first portion 146 of cylindrical member 142. A slight turning or twisting of the nut 170 draws the arbor 160- into the bore 150 to expand the slotted second portion 148 against the wall of the bore 156 to thereby rigidly connect the adjusting device 140 to the male member 124.

The number of adjusting devices 140 corresponds to the number of corresponding sets of cutting edge segments used for the polygonal cutting edges of the male and female members. In the illustrated embodiment, each polygonal cutting edge of the male and female members comprises three inter-related cutting edge segments; therefore, three adjusting devices 140 are employed.

' In operation, the cutting edge segments 126 and 130 can be adjusted to just contact each other or to be spaced very slightly from each other, as is desired. A good gauge to afford proper spacing of the cutting edge segments relative to each other is a thin piece of tissue paper placed between the cutting edge segments while adjusting. The cutting edge segments 126 and 130 are moved into contact with each other or just separated by a small fraction of an inch as by inserting the tissue paper therebetween. The adjusting device 140 is pulled toward the female member 122 until the annular ring 144 contacts the surface 157 of the shank portion 128. The nut 170 is then twisted to rigidly fix the adjusting device 140 to the male member .124 as previously described. This operation is repeated for each set of cutting edge segments.

In this manner, wear on the polygonal cutting edges is greatly reduced and practically eliminated because the engagement of the annular ring 144 with the surface 157 prevents excesive rubbing and frictional contact between the cutting edges. Thus cutting edge life is greatly increased.

This invention contemplates an externally adjustable device which can be selectively fixable to the female mem ber instead of the male member and which includes an annular ring or flange which engages the inner surface of the male shank portion to limit the spacing between cor-' responding cutting segments.

Various of the features of the invention are set forth in the following claims.

I claim:

1. An electric shaver comprising a first member having means defining a bore having an internal generally planar cutting edge of polygonal configuration, a second member carried by said first member and having means defining a peripheral cutting edge of polygonal configuration located within said bore and generally coplanar to said first mentioned cutting edge, and corresponding to and cooperable with said cutting edge defining means of said first member, an electric motor, and means operatively connecting said electric motor to one of said first and second members to afford relative movement therebetween in said plane to provide a whisker cutting action.

2. A shaving head comprising a first member having a central polygonal bore including means defining a series of cutting edge segments at the margins of said bore, a second member movably carried by said first member and having a raised portion of polygonal configuration corresponding to and received in said polygonal bore, said raised portion also including means defining a series of cutting edge segments at the outer margins of said raised portion coplanar with said cutting edge defining means of said first member, said first and second members each having annular lip portions, and means cooperating with said respective lip portions for moving said first and second members relative to each other to provide a cutting and slicing action between said first and second members.

3. A shaving head comprising a female member having a face portion adapted to engage the skin of a shaver and having a flat surface spaced from said face portion and including a first annular lip, said face portion having a triangular bore including angularly related surfaces at the margins of said bore defining a number of cutting edge segments, a male member located Within said female member and including a portion having a flat surface engaged with said surface of said female member to afford a sliding movement therebetween and including a triangular part raised from said flat surface of said male member, said triangular part being received in and congruent with said triangular bore, said portion including a second annular lip, said triangular part having a first surface coplanar with said face and having a series of second surfaces angularly related to said first surface to define a number of cutting edge segments at the periphery of said raised part and in the plane of said face, means for retaining said male and female members in sliding engagement with each other, and a rotatable element having oppositely extending arms, one of said arms engaging said first annular lip and the other of said arms engaging said second annular lip, whereby rotation of said cam affords relative movement of said malev and female members to provide a cutting and slicing action along the corresponding cutting edge segments of said first and second members.

4. The shaving head as set forth in claim 3 wherein said means for retaining said male and female members in sliding engagement with each other comprises a series of holes in said male member and a similar series of corresponding larger holes in said female member, bolts respectively received in said corresponding holes, and a lock washer and a lock nut threaded on the respective ends of said bolts to provide a clamping force between said male and female members.'

5. The shaving head as set forth in claim 3 wherein said first annular lip is concentric with said triangular bore and said second annular lip is concentric with said triangular raised part and wherein said spring cam includes oppositely extending longer and shorter arms, said longer arm presses against said first annular lip and said shorter arm presses against said second annular lip.

6. The shaving head as set forth in claim 3 wherein said male member includes a number of adjustable screw studs extending substantially parallel to said first surface between said first surface and said portion engaging said female member for limiting spacing between the corresponding cutting edge segments of said male and female members.

7. An electric shaver comprising a case including an outer member at one end of said case, said outer member having a central polygonal bore including means defining a series of cutting edge segments at the periphery of said bore and including a first annular lip portion, an inner member slidably carried by said outer member and having a raised polygonal part congruent with said polygonal bore and a second annular lip portion, said raised part being received in said polygonal bore and also having means at the outer periphery thereof defining a series of cutting edge segments coplanar with said cutting edge segments of said bore, an electric motor carried by sa d case and having an output shaft extending toward sa d inner member, and a rotatable spring cam carried by said output shaft and having a pair of oppositely extending arcuate arms of differing length, one of said arms engaging said first annular lip portion and the other of said arms engaging said second annular lip portion, whereby rotation of said cam by said motor provides movement of said inner member with respect to said outer member so as to effect a cutting and slicing action along the corresponding cutting edge segments of said inner and outer members.

8. An electric shaver comprising a case including an outer member at one end of said case, said outer member having a flat face portion adapted to engage the skin of a shaver and a surface spaced from said face portion, said face portion having a triangular bore including angularly related surfaces at the margins of said bore defining a number of cutting edge segments, an inner member located within said outer member and including a portion having a flat surface engaged with said surface of said outer member to afford sliding movement therebetween and including a triangular part raised from said flat surface of said inner member, said triangular part being received in and congruent with said triangular bore, said portion also including an annular lip, said triangular part having a first surface coplanar with said face and having a series of second surfaces angularly related to said first surface to define a number of cutting edge segments at the periphery of said triangular part and in the plane of said face, an electric motor carried by said case and having an output shaft extending toward said inner member, a rotatable spring cam carried by said output shaft and having an arcuate arm engaging said annular lip, and means for retaining said male and female members in sliding engagement with each other whereby rotation of said cam affords relative movement of said inner and outer members to provide a cutting and slicing action along the corresponding cutting edge segments of said first and second members.

9. A shaving head as set forth in claim 8 wherein said means for retaining said inner and outer members in sliding engagement with each other comprises a series of holes in said inner member and a similar series of corresponding larger holes in said outer member, bolts respectively received in said corresponding holes, and a lock washer and a lock nut threaded on the respective ends of said bolts to provide a clamping force between said inner and outer members.

10. A shaving head comprising a first member having means defining a bore having an internal generally planar cutting edge of polygonal configuration, a second member having means defining a peripheral cutting edge of polygonal configuration located within said bore and generally coplanar to said first-mentioned cutting edge, and corresponding to and cooperable with said cutting edge defining means of said first member, and engaged cooperating bearing surfaces on each of said members, said sur- 6 faces being located in parallel relation to the plane of said cutting edges for facilitating coplanar relative movement between said cutting edges of said first and second members.

11. A shaving head comprising a first member having a polygonal bore including means defining a series of cutting edge segments at the margins of said bore, each of said segments including a shank portion, a second member movably carried on said first member and having a raised portion of polygonal configuration corresponding to and received in said polygonal bore, said raised portion including means defining a series of cutting edge segments at the outer margins of said raised portion, each of said segments including a shank portion, and an adjusting device for limiting the extent of relative movement of said corresponding cutting edge segments of said first and second members, said adjusting device including aligned bores in said shank portions of said first and second members, a cylindrical member carried in one of said shank portion bores of one of said first and second members and extending through the aligned one of said shank portion bores in the other of said first and second members, said cylindrical member having a bore including a tapered portion, an annular flange thereon disposed to engage said shank portion in the other of said first and second members, a slotted portion generally coextensive with said tapered portion of said bore, and means for expanding said slotted portion against the wall of said aligned one of said shank portion bores in the other of said first and second members to provide selective rigid connection of said adjusting device to one of said first and second members to thereby limit the extent of relative movement of said first and second members and thereby avoid cutting edge segment wear.

12. A shaving head as set forth in claim 11 wherein said means for expanding said slotted portion includes an arbor received in said bore and having a tapered portion cooperating with said tapered bore portion, and means for moving said arbor into said bore comprising a knurled nut threadedly received on the end of said arbor and disposed to engage the end of said cylindrical member to thereby forcibly draw said arbor into said bore upon twisting said nut.

13. A shaving head as set forth in claim 11 wherein said aligned one of said shank portion bores in the other of said first and second members is enlarged to allow movement of said cylindrical member therein.

14. A shaving head as set forth in claim 11 including an adjusting device for each of the corresponding cutting edge segments of said first and second members.

References Cited UNITED STATES PATENTS 1,918,625 7/1933 Wills 3041.9 2,292,828 8/1942 Feyrer 3041.9 2,579,706 12/1951 Senders 3043.6 X 3,065,541 11/1962 Bauerle 3041.9

WILLIAM FELDMAN, Primary Examiner.

MYRON C. KRUSE, Examiner. 

1. AN ELECTRIC SHAVER COMPRISING A FIRST MEMBER HAVING MEANS DEFINING A BORE HAVING AN INTERNAL GENERALLY PLANAR CUTTING EDGE OF POLYGONAL CONFIGURATION, A SECOND MEMBER CARRIED BY SAID FIRST MEMBER AND HAVING MEANS DEFINING A PERIPHERAL CUTTING EDGE OF POLYGONAL CONFIGURATION LOCATED WITHIN SAID BORE AND GENERALLY COPLANAR TO SAID FIRST MENTIONED CUTTING EDGE, AND CORRESPONDING 